Report-back: Rain, Snow, and Record-Breaking Thresholds during Winter 2025–2026

April 2026 - Written by Katherine Moore-Powell

Precipitation patterns across the US during the 2025–2026 winter season highlighted a contrast between dry, warm western basins and storm-active eastern regions. This season wrap-up provides an overview of the seasonal weather patterns across Mountain Rain or Snow project regions. 

In contrast, large portions of the Western US experienced record or near-record low precipitation and snowpack (NOAA Snow Analysis, US Drought Monitor), ranking among the driest winters in decades. When winter storms did arrive, they were often warmer and with higher snowlines, producing rain at elevations that typically receive snow. This led to multiple rain-on-snow events and mid-season melting episodes, further reducing snowpack. Meanwhile, parts of the Midwest and Northeast experienced short but intense storms, with much of the season’s precipitation falling in just a few days, sometimes as heavy snow, and other times as mixed precipitation. Fluctuating temperatures delivered a wide range of precipitation types, including snow, sleet, freezing rain, and rain. Across the US, rapid transitions between rain, snow, and mixed precipitation within single storm events reinforced a key takeaway from this winter: precipitation was less consistent, more episodic, and increasingly sensitive to small temperature changes (National Centers for Environmental Information). 

Observations from the various Mountain Rain or Snow project regions exemplify this past winter’s record-breaking patterns across the country. In Colorado, the statewide snowpack dropped to record-low levels as much precipitation fell as rain rather than snow, leaving some mountain basins near the 0th percentile snow-water equivalent by Dec. 25, 2025 (SNOTEL observations).

In the Sierra Nevada, rain dominated early across the region. For example, rain made up the first 1200 reports of the winter around Reno, NV. The first snow observation was not made until Dec 19th, and the majority of snow and mix reports occurred on or after Dec 24th.

When seasonal weather patterns depart from normal, sometimes marginal, or threshold, conditions are key to understanding why so many records were challenged or broken. This winter, sometimes even small temperature differences shifted precipitation type to either majority snowfall or majority rainfall, influencing whether storms contributed to snowpack or immediate runoff. 

Additionally, this past winter season underscores a critical shift in winter precipitation, where records are no longer defined solely by how much precipitation falls, but by how it falls, how quickly it arrives, and how often it deviates from historical norms, especially in mountain environments (NOAA National Environmental Satellite, Data, and Information Service or NESDIS).

Your commitment to Mountain Rain or Snow is crucial to advancing and expanding our understanding of winter weather, its impacts, and, in the long run, our ability to be better prepared for anomalous winters like these. Our team is grateful for your observations and continued dedication to the project!